235/45R21
Standard MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
The 235/45R21 tire size features an overall diameter of 29.33 inches, a section width of 9.3 inches (235mm), and rotates 688 times per mile. It is a standard factory tire fitment on 7+ vehicle models including Audi Q4 e-tron, Audi Q4 e-tron Sportback.
Physical Dimensions & Specs
Overall Diameter
29.33"
745.0 mmSection Width
235 mm
9.25" wideSidewall Height
4.16"
105.7 mm (45% aspect)Revolutions / Mile
688
Circumference: 92.13"Rim Diameter
21"
Wheel sizeRecommended Rim Width
5.9" - 8.2"
Optimal rim width rangeWhere to Buy & Install 235/45R21 Tires
Looking for 235/45R21 tires? Skip hauling tires in your car—choose direct delivery to a local certified shop or doorstep delivery:
Tire Rack
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Amazon Automotive
Fast doorstep shipping for DIYers or bringing to your own shop.
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Speedometer & Alternate Size Calculator
Testing an alternate size for your vehicle? Compare 235/45R21 against any proposed tire size below:
Visual Tire & Wheel Comparison
Speedometer Variance
| Indicated | Actual Speed | Diff |
|---|---|---|
| 20 mph | 20.2 mph | +0.2 mph |
| 30 mph | 30.3 mph | +0.3 mph |
| 45 mph | 45.4 mph | +0.4 mph |
| 60 mph | 60.5 mph | +0.5 mph |
| 75 mph | 75.6 mph | +0.6 mph |
| 90 mph | 90.8 mph | +0.8 mph |
Fender & Suspension Clearance
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Vehicles That Fit 235/45R21 (7+ Models)
Factory standard and optional vehicle fitments utilizing 235/45R21 tires: